Webster's Revised Unabridged Dictionary · 1913

Zygodactylic

Zygodactylic , adjective

[Greek zygo`n a yoke, pair + {not transcribed} finger, toe: compare French zygodactyle.]

(Zoology) Yoke-footed; having the toes disposed in pairs; -- applied to birds which have two toes before and two behind, as the parrot, cuckoo, woodpecker, etc.

Also: Zygodactylous